Advice on what to do to resolve codes

[ewill3rd]

If you really have 10 psi, no amount of leakage from the FPR would be the cause.
There is only one possibility related to the FPR but... it would never have left the techs bay that installed the fuel rail. If the center small o-ring is left out the pressure will be too low but as I said, you wouldn't have been able to drive it before. Our relays (GM's) are pretty robust. I can probably count on my hands the number of bad relays I have really replaced over the years. (yeah, I'm not kidding)
If the fuel pump runs it should generate higher pressure. The only remaining possiblity I see based on your diagnosis is a lack of fuel. Is there actually gas in the tank? The fuel gage could be lying.
Otherwise I'd say you need to put a fuel pump in it, It is wise to be wary if you are nervous about the procedure required. Look around for a reputable shop and let them do it would be my advice.

[Ranger]

I bought a fuel pressure gauge as suggested by ewill3rd. 10 psi after key to on position; 10 psi while turning over trying to start.

There's your problem. Like Ewill said, it's pump time.

[Mark C]

Since the car started immediatly after replacing the fuel filter, and seemed to run fine, but then got progressively worse until it died, pull the new fuel filter out and drain it onto some paper see if its loaded with garbage. Almost sounds like the filter plugged up in that 5 minutes or so that the car was running. If it doesn't have junk in it then your probably looking at a new pump but I'd check out the filter again before spending a ton of dough on a new fuel pump. If you've got a bunch of garbage in the tank you'll need to get it out, it can't be helping the pump any.

[wachuku]

pull the new fuel filter out and drain it onto some paper see if its loaded with garbage

Thanks for suggestion. Followed it, but all appears clean.

If you really have 10 psi...

My thoughts as well. So I slapped the fuel pressure gauge on a '97 Saturn, turned the key to on position w/ engine off, and obtained an immediate 40 psi. From which I draw two inferences: (1) I appear capable of properly administering a fuel pressure test; (2) 10 psi might even be on the high side for my car (based on personal observations of my particular gauge).

If the center small o-ring is left out the pressure will be too low

The center small O-ring is present.

The only remaining [possibility] I see based on your diagnosis is a lack of fuel

There's fuel in the tank -- and on me, and on the ground below my fuel filter.

Look around for a reputable shop and let them do it would be my advice.

Advice that is probably sage. Nonetheless I intend to attempt to replace the fuel pump myself. I've been under the vehicle, disconnected the electrical to what I presume will be the fuel pump, and I've successfully turned (loosened) three of the four tank strap bolts. The fourth and final bolt is beneath the exhaust shield, but I believe I will be able to access it and loosen it tomorrow (mosquitoes too bad tonight).

Some Questions:

• Is there some sort of back-flow stop-valve where the fuel filler neck interfaces with the tank? I believe my tank is near 3/4 full; do I need to remove fuel to prevent spill when tank-to-neck interface is disassembled? On the other hand, there are pictures of "dropping the tank" for a '94 Eldo in the link below, and apparently fuel filler lines are left attached -- but if so, it seems they must be on passenger side for '94 eldo. On my car exhaust shield is on passenger side and fuel filler lines are on driver side, and I don't see how I could lower and tilt tank towards driver side with filler lines attached. In my case should I tilt towards exhaust shield (passenger) side while filler lines remain attached on driver side?
• http://www.cadillacforums.com/forums...tructions.html (Fuel pump replacement instructions)
• The metal part of the fuel neck on my vehicle is rusted; should I attempt to replace the neck at this time? Is the metal neck removable without disassembling several suspension components? (I prefer not to replace unless rust indicates corrosion problem likely before a conservative 100,000 mi / 10 yr from now).
• How tall is a '97 fuel pump? I have my car on jack stands so tires are 1-2 inches above ground; will this be high enough even with tank lowered all the way to the ground?

[N*Caddy]

The fuel pump is about 8 to 9 inches tall (I am sorry I don’t have the exact measurement, this is what I remember). You should probably lift the car a little bit higher.
The fuel tank should be as empty as possible (that’s what I would recommend).
To drop the tank you will also disconnect the filler neck rubber hose from the tank (you can not see from those pictures because the hose connects in the back).
You can change the filler neck later but be aware of the cost! Is something like $500 for the actual filler neck and $98 for the hose between the filler neck and fuel tank.
Unfortunately I did not changed the fuel pump myself (on my car, I changed in other GM vehicles), but I know that my mechanic was complaining about me having the tank full (when my pump failed I was just going to fill up).
My God Wachuku, you’ve been everywhere I was!

[ewill3rd]

I don't think that tank has an anti-siphon valve in it, if you think it has that much gas, try to get some out.
You'll need to lower it on the left and slide it out, with the fill hoses disconnected you might end up taking a bath.
Lower the heat shield. There should be several 7mm fasteners holding it to the body, just the rear portion needs to come loose, you need not remove it, just lower it.
I use a swivel socket to get to that front bolt.
Raising the car up as high as you can is good, use jackstands to be safe if you have them.
If the rust is so bad the paint is bubbling off and you think you could punch a hole in the filler neck now might be a good time to look for one. Some rusting is normal and unless the metal is just crumbling you might let it go for now.
The lines are attached to the pump on top, the best way to do it is to disconnect the pressure and return lines near the filter, then find and disconnect the EVAP canister hoses, drop the tank with the lines attached but be sure they are disconnected from the lines on the vehicle.

The procedure on replacing the filler neck usually isn't a big deal but on your specific vehicle I don't think I have ever changed one so I can't offer you much in the way of advice.

[N*Caddy]

Oh, first you drain the tank then you lower it, I mean why would you drain it once lowered. Since is ¾ full, getting the filler neck hose out will not spill any gas. Insert a hose in and drain the tank, then lower-it. Since the filler hose goes in the left rear side of the tank, once tilted to the left most of the gas will rush trough the filler hole.

[kdcing]

I'd recommend siphoning the gas from the tank. At 3/4 full and at about 8# per gallon, there is about 120# of fuel in the tank. With a full tank, dropping the tank will not be the issue,however, raising it back up and positioning it will be a challenge (especially w/ 120# sloshing and shifting position). The tank itself is light (i.e. plastic)...an empty tank can be positioned back into place by 1 person, but is somewhat cumbersome due to its size.

Every pump replacement that I've seen has been w/ the tank dropped/slanted to the driver's side....most have had the fuel inlet lines disconnected, however, I've seen the pictures of the lines not disconnected....which may stress the lines.

The FP is actually inside a round plastic cup-type piece....the cup contains the fuel guage sending unit. When you drop the tank, you will be removing the entire assembly (i.e. sending unit + FP). The FP is probably 6" tall...the sending unit is probably 9-12" tall....the higher you can jack the car, the better. Here is where it really helps to disconnect the fuel inlet lines...if they are removed, you can totally slide the tank out from underneath the car to more easily remove and replace the sending unit's holdown ring. Btw...the FP alone is $85-$100, the FP + Sending unit is $200-$250 (pricing for a '93 Eldorado, but should be similar for a '97 STS).

If you have a pick-it-yourself junkyard nearby, it may be worthwhile to visit. Before my 1st FP replacement, I visited the nearby yard and found several Caddy's w/ the tanks in various stages of removal. It was an hour well spent to prepare for the surgery. Btw, the yard near me punctures and drains the tank (for epa reasons), so my leason at the yard was cleaner/easier/safer.

[submariner409]

Just a FYI for weights and measures.......in American units, gasoline is 6#/gal., diesel is 7#/gal, fresh water is 8.32#/gal, and sea water is 8.56#/gal. ..........(Not being snitsy.....just old submarine ballasting info....)

[N*Caddy]

Kdcing, you made me dig for the filler neck bill, here is it:
Fuel Filler Neck Ass. (The metal part) ……… 519.99 + taxes
Fuel Filler Neck Hose to Tank ……………....…..98.75 + taxes
I was also charged 1 h of labor.
Keep in mind, the above prices are Canadian:lesley:, probably some 20% over the US prices.

That’s a VERY, VERY GOOD advice with the junkyard, best place to learn!

[kdcing]

Originally Posted by submariner409

Just a FYI for weights and measures.......in American units, gasoline is 6#/gal., diesel is 7#/gal, fresh water is 8.32#/gal, and sea water is 8.56#/gal. ..........(Not being snitsy.....just old submarine ballasting info....)

...hmm...I'm surprised the military has the weights for those liquids...it was my understanding to keep the troops' moral high, the ballasts were actually filled with beer

[wachuku]

Fellas--

'Preciate all the help -- from the diagnostics to the how-to's and the extra tips.

Based on what you guys explained, I was able to remove the old fuel pump and install a new one. The new pump is working, including its fuel level gauge.

Fuel pressure measures at 43 psi at idle, and for the first time since I've owned the car, the anti-lock breaking system was engaged unintentionally: I was a little overzealous in testing the pump at high speeds (if it even matters).

I'm tired; replacing the pump took me all day; and although everything didn't go completely smoothly, I doubt I experienced anything that isn't already posted somewhere on this forum; so I'll forgo any type of recap -- at least for tonight.

Thanks again fellas, your help has been both accurate and invaluable.

Later this week I'm hoping to tackle the serpentine tensioner, and then later it's on to the A/C compressor...

[ewill3rd]

You have already finished the hard one.
The other things you mentioned are a lot easier.

Glad to hear she's running again!

[Tracie3101]

I am probably in the wrong section- this is the first time I have been on this site. I have a 2003 Deville and I had a tire that lost almost all of it's air and as a result I had three warning lights come on my dash 1)Emergency brake on 2) abs 3)traction control. How do I get these lights to go off. I was told it was a case of resetting the codes but I have no idea how or what to do.

[submariner409]

Tracie 3101, Go to "Past Deville" (next forum down) and ask your question, and also look either just above this thread or in Past Deville, at the top, for "How to pull codes", then go down to Cadillac Technical, Northstar Performance, and look at the top for "Got Codes? Look Here".